Zero Carbon Building Christopher TO Construction Industry Council - - PowerPoint PPT Presentation

Zero Carbon Building

Christopher TO Construction Industry Council

Construction Industry Council

• Set up under the Construction Industry Council Ordinance (Cap.587)
• Functions of the CIC are stipulated in Sections 5&6 of the

Construction Industry Council Ordinance (Cap.587)

2

Enhance Cohesiveness

Functions

• f CIC

Enhance Cohesiveness Advance Skills Through Training Elevate the Quality and Competitiveness Promote Good Practices Reflect Needs and Aspirations

Introduction

• Promoting the ongoing development and

improvement of industry

• Encouraging research activities and the use of

innovative techniques and to establish or promote the establishment of standards for the construction industry

• Promoting good practices in the construction

industry in relation to…, environmental protection,…

Background

• Hong Kong Government has recently targeted for

Carbon Reductions (50% to 60% Carbon Intensity Reduction by 2020 compared to 2005 baseline)

• Buildings consume 90% electricity and are responsible

for 60% Greenhouse gases (GHG) emissions in HK – Construction industry has a significant role to play in GHG emission reduction

Objectives

Serving as an exhibition and education centre

• To showcase the state-of-the-art eco-building design and

technologies to the construction industry internationally and locally as well as to raise community awareness of sustainable living in Hong Kong

• To promote the green living and working and the human

behavioural changes which can contribute to the GHG emission reduction

8 Sheung Yuet Road Kowloon Bay

Kowloon East

D-01

Cafe

Eco-Plaza

Urban Native Woodland:

Biodiversity in urban area

ZCB

Commercial Area Shop

Eco-Terrace

Outdoor Exhibition Areas

Landscape Master Plan

D-01

Hopefully, in 2 years’ time…

Basement / Ground Floor Plan

Ground Floor Plan

Ground Floor Plan

Ground Floor Plan

Ground Floor Plan

Mezzanine Floor Plan

Mezzanine Floor Plan

Programme

• Inception

Oct 2010

• Commencement of Study and Design Apr 2011
• Commencement of construction

July 2011

• Project completion

Jun 2012

• Official opening

Jun 2012

• Public opening

Sep 2012

Significance of ZCB

• 1st zero-carbon building in HK
• 1st building with grid feed-in in HK
• 1st native urban woodland in HK
• One of the 1st BEAM Plus Platinum new building

projects

• 1st large scale use of biodiesel made from waste

cooking oil for electricity generation

• One of the few ZCBs in the world that account for

carbon emissions during the operation stage as well as the embodied carbon of the construction process and the major structural materials

Key Features

• Carbon neutral
• Energy positive
• Climate positive
• Experimenting
• Evaluating
• Evolving
• Educating

Key Design Features

Outdoors

High Greenery Coverage Urban Native Woodland Eco-paver and Grasscrete as Pervious Surfaces Air Tree

Passive Design

Climate-responsive Built Form and Orientation Ultra-Low Overall Thermal Transfer Value (OTTV) High Performance Glazing System Wind Catchers and Light Pipes Earth Cooling Tube

Active Systems

High-Volume-Low- Speed Fans High Temperature Cooling System Smart Controls / Building Management System Microclimate Monitoring Stations

Zero Carbon Renewable Technologies

Bio-fuel Tri- generation Plant Photovoltaic Low Embodied Carbon Materials Low Embodied Carbon Construction

Others

Water Use Management Thematic Showcases for Eco-workplace and Sustainable Living

Design Strategy – Climate Positive

Greenery + Cool Materials

Key Design Feature High Greenery Coverage

• About 50% for greenery coverage of the site,

including vertical greening

• Tree ratio at about 200 trees per hectare
• Existing mature trees within the site in good

conditions are preserved.

• The high degree of greenery serves as “carbon

sink” to absorb carbon dioxide as well as “heat sink” to cool summer prevailing winds and reduce the heat island effect.

Key Design Feature Urban Native Woodland

• Over 150 native trees, with over 40 different species

in the woodland

• Native woodland area of about 2,000m2 (over 20% of

the site)

• Diversity of native species enhances biodiversity to

provide food and shelter to attract native wildlife into the city.

Key Design Feature Eco-Paver and Grasscrete

• Act as pervious surfaces which allow water

permeation and act as cool materials to help reduce heat island effect

• Eco-paver has a top layer with titanium dioxide

which has the added value for air pollutant removal

Key Design Feature Air Tree

• A covered walkway system

cladded with sustainable timber providing shade, cooling air breeze and a framework for climbing plants

• Cooling breeze is accentuated

by ceiling fans

• Reduction of uncovered

impervious surface and associated heat island effect

Key Design Feature Climate-responsive Built Form & Orientation

• Optimize beneficial use of wind, sun and daylight
• Reduce the demand for mechanical heating/cooling

and artificial lighting

• Main façade facing SE to capture prevailing summer

breeze

• Tapered built form to draw stronger airflow across

the building and to reduce exposure solar heat gain from the south façade and increase daylight from the north façade

• Elongated built form to reduce façade areas towards

the East and West

Key Design Feature Ultra-Low OTTV

• The lower the overall thermal transfer value (OTTV),

the smaller the solar heat gain through building fabric and the cooling load for air conditioning

• OTTV of ZCB at 11W/m2, about 80% lower than

statutory requirement at time of completion

• Due to optimized window-to-wall radio, deep
• verhang over the south façade, external shading

fins, minimized east and west facades/windows, high performance glass wall system, and shaded and insulated roof

Key Design Feature High Performance Glazing System

• To lower cooling load and reliance on artificial

lighting

• U value is kept as low as 1.6 W/m2 based on the

Insulated Glazed Unit construction with low-e coating

• Low Shading Coefficient (SC) at 0.33 and relatively

high Visual Light Transmittance (VLT) at 0.54

Key Design Feature Wind Catchers & Light Pipes

• On top of the design for cross ventilated and

daylight layout, wind catchers and light pipes are provided on the rooftop to enhance natural ventilation and daylighting for areas furthest away from windows

Key Design Feature Earth Cooling Tube

• Provided near the building for

pre-cooling of fresh air by making use of the cooler thermal mass of the earth

• Reduce cooling load and

energy use due to the passive pre-cooling of the incoming air

• The temperature difference

between the air and the earth mass in the summer at about 5ºC maximum.

Key Design Feature

High-Volume-Low-Speed Fans

• Patented blades design to enhance evaporation

for comfort

Key Design Feature High-Temperature Cooling System

• Comprises chilled beams, underfloor displacement

cooling and desiccant dehumidification

• Higher supply air temperature allowing greater

extent of free-cooling (number of hours suitable for free cooling increases from 200 hours to 600 hours each year)

Key Design Feature Smart Controls/ BMS

• The building monitors itself constantly, so that

the active and other building systems can be evaluated and optimized for their operation and environmental performance

Key Design Feature Microclimate Monitoring Stations

• 4 micrcoclimate monitoring

stations are placed on and around the building to evaluate how the building performs and interacts with its surroundings

• These monitoring stations offer

critical data to the Intelligent BMS for optimization of building environmental performance in response to actual microclimatic conditions.

Key Design Feature Water Use Management

• 3 Eco-toilets making use of

waterless urinals, low-flow sanitaryware and grey water recycling

• 1 toilet is equipped with black

water recycling treatment

• Stormwater harvesting
• Artificial wetland with subsurface

flow to treat grey water/stormwater by the roots of plants

Renewable Active Systems

Energy Hierarchy

Energy Strategy

Reduction of Energy Demand

Passive Design Active Systems

20% 25%

Renewable Energy Generation

Biodiesel Tri- generation System PV Panels

• multi-

crystalline

• BIPV
• CIGS

Solar Water Heating

Renewable Energy Bio-fuel Tri-generation Plant

• 1st large-scale use of bio-diesel as a renewable tri-

generation (a combined Cooling, Heating and Power <CCHP> system)

• Waste-to-energy (bio-diesel produced from waste

cooking oil)

• Generate 143 MWh per year
• Capture 70% of the fuel energy (adsorption cooling /

desiccant dehumidification), compared to 40% for conventional energy supply through grid electricity where the bulk of fuel energy is rejected into the sea

• r atmosphere.

CCHP

Power + Cooling + Dehumidification

Renewable Energy Photovoltaic

• Solar irradiance of the whole site with reference to

surrounding context and neighbouring buildings has been studied to determine the best location for the building to receive the solar energy

• Generate 87 MWh per year (over 60% of ZCB

consumption)

• 3 different types of PV are used:

– 1015m2 multi-crystalline on the inclined roof (about 80% of the roof) – BIPV-thin film covering the viewing platform, and – cylindrical CIGS thin film integrated in the air tree

Multi-Crystalline BIPV CIGS

Emissions during operation 50 years Emissions during construction Emissions embodied in materials On-site renewable energy offset 8,080 tonnes (161 tonnes per year) 150 tonnes 1,400 tonnes

Energy Plus

4,600 tonnes

(92 tonnes per year)

Net energy output over operating energy consumption to offset embodied carbon of major structural materials & construction

Total 6150 tonnes 8,080 tonnes

Carbon Strategy

Low Embodied Carbon Materials

• Regionally manufactured

materials

• Sustainable timber
• Reinforced concrete with steel

rebar with recycled content and high percentage of Pulverized Fly Ash

Consume less energy or emit less carbon in their process of extraction, manufacturing and transportation

Low Embodied Carbon Construction

• Balanced cut and fill for the site formation works
• Gabion wall construction making use of construction

debris salvaged from demolition

Performance

Construction Stage – CO2 Reduction

Reference CO2 Emission Target CO2 Emission of This ZCB Reduction Construction Process 2200 t 150 t 30% Material Use 1400 t

Performance

Operation Stage – CO2 Reduction and Energy Savings in Building

Typical Design Building CO2 Emission 140 t/yr Building Energy Consumption 200 MWh/yr Measures Taken in Design to Reduce CO2 Building CO2 Reduction (ton CO2/yr) CO2 Reduction (% of total building) Building Energy Saving (MWh/yr) Energy Saving (% of total building) Envelope design 6 4 9 4 Ventilation design 10 6 14 6 Lighting design 33 20 47 20 Cooling design 27 16 38 16 Total Reduction 76 46 108 46 CCHP Generation 81 48 143 (generated) N/A PV Generation 61 36 87 (generated) N/A Energy Consumption: <100 kWh/sqm/yr 46% less than the baseline of HK’s Building Energy Code (BEC)

Thank You

E-Mail: zcb@hkcic.org http://zcb.hkcic.org